Colt CR-Series Carbine 5.56mm NATO, 16 in, A4 Flat-Top, 1:7 Twist, MP-Marked Barrel, Sightmark Ultra Shot M-Spec (2021)
This Colt CR-series Carbine is a 2021 production AR-15 platform rifle with the less-common CR-prefix CARBINE rollmark. It features a 16 in MP-marked, 1:7 twist barrel with an A2 flash suppressor, an A4 flat-top upper with T-marked Picatinny rail, and a carbine-length gas system with a fixed A-frame front sight base. Factory identifiers include the Colt CAGE code 13629 on the barrel and a modern 2D data-matrix code on the lower. A Sightmark Ultra Shot M-Spec reflex sight is installed, and a 30-round Magpul PMAG is included.
Condition
Overall Condition: Good condition, showing some signs of prior use and handling.
Bore Condition: Good - Clean, well-maintained, minor wear marks.
Rifling: Good Rifling - Intact, well-defined lands and grooves.
Specific Condition Notes: There is some pitting on the flash hider. Mild scuffs and scratches are present throughout.
What’s Included
- Sightmark Ultra Shot M-Spec reflex sight (installed)
- 1x 30-round Magpul PMAG polymer magazine
The CR-prefix CARBINE rollmark distinguishes this rifle within Colt’s modern lineup, offering a variant that is less commonly seen than the typical M4 CARBINE marking. The lower receiver also carries a 2D data-matrix code, reflecting current Colt manufacturing and identification practices.
The 16 in steel barrel uses a 1:7 twist suited to common 5.56mm NATO loads and is MP-marked. It is threaded and fitted with an A2 flash suppressor. The barrel shows Colt’s CAGE code 13629, and the rifle operates via a direct-impingement system with a rotating bolt and a carbine-length gas system.
The A4 flat-top upper provides a T-marked Picatinny rail for mounting optics. A fixed A-frame front sight base with bayonet lug and sling swivel is installed; no rear sight is included. The rifle accepts STANAG-pattern magazines and has a 30+1 capacity.
Furniture includes a telescoping polymer stock with a 13.0 in length of pull and two-piece carbine-length ribbed polymer handguards. The aluminum-alloy receivers wear a hard-anodized black finish, and controls include a manual safety. A Sightmark Ultra Shot M-Spec reflex sight is already mounted for immediate use.